1. Field of the invention
The present invention concerns a metal stamping tool with working parts that can be removed while on the machine, especially intended for carrying out operations upon sheet metal pieces.
2. Description of the prior art
For manufacturing pieces in sheet metal, tools are normally used that are fitted upon stamping machines in order to carry out punching, stamping, cambering, etc. operations. These tools usually each comprise working parts such as stamps and matrixes that are subjected to more or less rapid wear, holding pieces such as stamp-holders, matrix-holders, attachment blocks that are respectively mounted upon the slide and the table of the stamping machine, and a blank-holder usually intended both to secure firmly in position a sheet metal piece undergoing a shaping and in guiding these stamps within their sliding. Due to the fact that these stamps are more or less brittle, stamping tools are currently conceived in such a way that during rest or at the end of their withdrawal or disengagement stroke, the ends of their stamps still remain partially engaged within the guiding holes formed within their blank-holder. This means that during operations for their replacement, change or service maintenance, these stamps cannot be removed while the tools are still on the machine, i.e. in position upon the stamping machines. Accordingly, a replacement, service maintenance or change of stamps and matrixes in these known tools cannot be carried out while on the machine, it presents a loss of working time and relatively high man-power costs.